论文标题
通过控制HBN封装的MOS $ _2 $中的载体浓度来暴露TRION的良好结构
Exposing the trion's fine structure by controlling the carrier concentration in hBN-encapsulated MoS$_2$
论文作者
论文摘要
原子上薄的材料，例如半导体过渡金属二核苷，对环境高度敏感。这为通过更改周围环境而开辟了一个机会来控制其财产。在这项工作中，从HBN封装的单层MOS $ _2 $组装的高质量范德华异质结构借助光致发光，光致发光激发和反射率对比实验来研究。我们证明，MOS $ _2 $单层中的载体浓度是由底物中的杂质转移引起的，可以通过修改底部HBN薄片厚度的修饰来显着调节一个数量级。研究结构的特征是光谱线接近较窄的均质宽度极限，从而可以观察到激发复合物的微妙光学和自旋 - 谷化特性。我们的结果使我们能够在MOS $ _2 $单层中解决三个光学活性负电荷的激烈式激子，它们分配给了Interavalley Singlet，Intervalley Singlet和Intervelley Triplet States。
Atomically thin materials, like semiconducting transition metal dichalcogenides, are highly sensitive to the environment. This opens up an opportunity to externally control their properties by changing their surroundings. In this work, high-quality van der Waals heterostructures assembled from hBN-encapsulated monolayer MoS$_2$ are studied with the aid of photoluminescence, photoluminescence excitation, and reflectance contrast experiments. We demonstrate that carrier concentration in MoS$_2$ monolayers, arising from charge transfer from impurities in the substrate, can be significantly tuned within one order of magnitude by the modification of the bottom hBN flake thickness. The studied structures, characterized by spectral lines approaching the narrow homogeneously broadened limit enabled observations of subtle optical and spin-valley properties of excitonic complexes. Our results allowed us to resolve three optically-active negatively charged excitons in MoS$_2$ monolayers, which are assigned to the intravalley singlet, intervalley singlet, and intervalley triplet states.
